CN112542553A

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Info

Publication number: CN112542553A
Application number: CN201910893806.0A
Authority: CN
Inventors: 程陆玲
Original assignee: TCL Research America Inc
Current assignee: TCL Research America Inc
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2021-03-23
Anticipated expiration: 2039-09-20
Also published as: CN112542553B

Abstract

The invention discloses a compound and a preparation method thereof and a quantum dot light-emitting diode, wherein the quantum dot light-emitting diode comprises an anode, a quantum dot light-emitting layer, an electron transmission layer and a cathode, the quantum dot light-emitting layer is arranged between the anode and the cathode, the electron transmission layer is arranged between the quantum dot light-emitting layer and the cathode, the electron transmission layer comprises organic molecules and metal oxide nanoparticles, and the organic molecules are anthocyanin-like organic molecules or furan series compound organic molecules. According to the invention, after the solid film is formed by the anthocyanin-like organic molecules or furan compound organic molecules and the metal oxide nanoparticles, the charge transmission performance of the metal oxide nanoparticle solid film can be effectively improved, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

Description

Compound and preparation method thereof and quantum dot light-emitting diode

Technical Field

The invention relates to the field of quantum dot light-emitting devices, in particular to a compound and a preparation method thereof, and a quantum dot light-emitting diode.

Background

Quantum dot light emitting diodes are another breakthrough of the next generation of novel display technology, but the quantum dot light emitting diode technology needs to solve many technical problems before industrialization, such as device lifetime, device efficiency, and the like.

Many more complex technical problems are involved in the service life of the quantum dot light-emitting diode device, and factors which can influence the service life attenuation of the quantum dot light-emitting diode device include stability problems of a light-emitting material, conductivity problems of a charge transport layer of the device, packaging problems of the device, interface charge accumulation and the like.

The problem of charge conductivity of quantum dot light emitting diode devices relates to two transport layers of electrons and holes, and in the quantum dot light emitting diode devices, the electrons are easy to change when transported by the electron transport layer, so that the electron conductivity is poor. In the process of implementing the present invention, the inventor researches and discovers that the possible main factor is that the electron transport layer is a solid film formed by metal oxide nano-particles, and the surface of the metal oxide nano-particles contains a hydroxyl group or a carboxyl group (-OH/-COOH), and the functional group has great influence on the conduction performance of the device. And the hydroxyl or carboxyl is relatively influenced by some factors such as heat, electricity, light and the like, the functional group on the surface of the metal oxide nano-particle after forming the solid film can change under the influence of the factors to further cause the deterioration of the electron transmission performance, and the change can be that hydrogen bonds are generated between the hydroxyl or carboxyl on the surface, so that the conductive electrons in the metal oxide nano-particle are adsorbed by hydrogen atoms on the surface of the metal oxide nano-particle.

In the prior art, atmosphere treatment is mainly carried out on the metal oxide nano solid film by using gases with reducibility to reduce the change of the solid film, but the process treatment is relatively troublesome and the repeatability of the treatment effect is relatively poor.

Accordingly, the prior art is yet to be improved and developed.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention aims to provide a composite, a preparation method thereof and a quantum dot light emitting diode, which aims to solve the problem that the electron transport performance is deteriorated due to some changes of the functional groups on the surface of the solid film formed by the existing metal oxide nanoparticles.

The technical scheme of the invention is as follows:

a method of preparing a composite, comprising:

providing organic molecules and metal oxide nanoparticles, wherein the organic molecules are anthocyanin-like organic molecules or furan-series compound organic molecules;

mixing the organic molecules, the metal oxide nanoparticles and a solvent to obtain a mixed solution;

and heating the mixed solution to obtain the compound.

A composite, comprising an organic molecule and metal oxide nanoparticles, wherein the organic molecule is an anthocyanin-like organic molecule or a furan-based compound organic molecule.

A quantum dot light-emitting diode comprises an anode, a quantum dot light-emitting layer, an electron transmission layer and a cathode, wherein the quantum dot light-emitting layer is arranged between the anode and the cathode, the electron transmission layer is arranged between the quantum dot light-emitting layer and the cathode, the electron transmission layer comprises organic molecules and metal oxide nanoparticles, and the organic molecules are anthocyanin-like organic molecules or furan compound organic molecules.

A method for preparing a quantum dot light-emitting diode comprises the following steps:

providing an anode, and preparing a quantum dot light-emitting layer on the anode;

preparing an electron transport layer on the quantum dot light emitting layer;

preparing a cathode on the electron transport layer to obtain the quantum dot light-emitting diode;

alternatively, providing a cathode, preparing an electron transport layer on the cathode;

preparing a quantum dot light emitting layer on the electron transport layer;

preparing an anode on the quantum dot light-emitting layer to obtain the quantum dot light-emitting diode;

the electron transport layer comprises organic molecules and metal oxide nanoparticles, wherein the organic molecules are anthocyanin-like organic molecules or furan compound organic molecules.

Has the advantages that: the composite is formed by the anthocyanin-like organic molecules or furan-series compound organic molecules and the metal oxide nanoparticles, and the composite is used as a charge transport material, so that the charge transport performance of a metal oxide nanoparticle solid film can be effectively improved, and the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

Drawings

Fig. 1 is a schematic flow chart of a method for preparing a composite according to an embodiment of the present invention.

Fig. 2 is a schematic flow chart of a method for manufacturing a quantum dot light emitting diode according to an embodiment of the present invention.

Fig. 3 is a schematic flow chart of a method for manufacturing a quantum dot light emitting diode according to another embodiment of the present invention.

Fig. 4 is a schematic view of the structural formula of procyanidins in example 1.

FIG. 5 is a schematic diagram of the structural formula of furan in example 2 according to the present invention.

Detailed Description

The invention provides a compound, a preparation method thereof and a quantum dot light-emitting diode, and the invention is further described in detail below in order to make the purpose, technical scheme and effect of the invention clearer and clearer. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Fig. 1 is a schematic flow chart of a method for preparing a composite according to an embodiment of the present invention, as shown in fig. 1, which includes:

s11, providing organic molecules and metal oxide nanoparticles, wherein the organic molecules are anthocyanin-like organic molecules or furan compound organic molecules;

s12, mixing the organic molecules, the metal oxide nanoparticles and a solvent to obtain a mixed solution;

s13, heating the mixed solution (in order to remove the solvent) to obtain the compound.

In this example, the mixing conditions are related to the mixing amount of the organic molecule and the metal oxide nanoparticles, the temperature, the time, and the environment.

In one embodiment, the ratio of the organic molecule to the metal oxide nanoparticles in the mixed solution is (0.1 to 10mmol):100 mg.

In one embodiment, the temperature of the mixing is 20 to 100 ℃. The dissolution of organic molecules can be efficiently achieved in this temperature range.

In one embodiment, the mixing time is 5 to 60 min. Sufficient mixing of the organic molecules with the metal oxide nanoparticles can be effectively achieved within this time frame.

In one embodiment, the mixed environment is an inert atmosphere.

In one embodiment, the concentration of the metal oxide nanoparticles in the mixed solution is 5 to 60 mg/ml.

In one embodiment, the solvent is a polar solvent, and may include, but is not limited to, one or more of an alcohol solvent, a nitrile solvent, and derivatives thereof. Particularly preferably, the solvent is an alcoholic solvent, and may include, but is not limited to, one or more of monohydric alcohol, polyhydric alcohol, and aromatic alcohol, and specifically may include, but is not limited to, one or more of methanol, ethanol, ethylene glycol, propanol, propylene glycol, glycerol, isopropanol, butanol, pentanol, hexanol, cyclohexanol, n-butanol, benzyl alcohol, and phenethyl alcohol.

The embodiment of the invention provides a compound, which comprises an organic molecule and metal oxide nanoparticles, wherein the organic molecule is an anthocyanin-like organic molecule or a furan compound organic molecule.

In one embodiment, the composite is comprised of an organic molecule and metal oxide nanoparticles.

The inventor researches and discovers that when the metal oxide nanoparticles form a solid film, hydrogen bonds are generated among functional groups (hydroxyl, carboxyl, amino and sulfydryl) only on the surface when other organic molecules do not exist among the metal oxide nanoparticles, and electrons conducted by the metal oxide nanoparticles are promoted to be adsorbed by hydrogen in the hydrogen bonds by the presence of the hydrogen bonds, so that further transmission of the electrons is hindered.

In this embodiment, an organic molecule is added to the metal oxide nanoparticle, where the organic molecule may be an organic molecule containing an anthocyanin, and when the molecule and the metal oxide nanoparticle form a solid film, a functional group on the surface of the metal oxide nanoparticle and a hydroxyl group (-OH) in the anthocyanin-like organic molecule can form a hydrogen bond, but since the anthocyanin-like organic molecule contains a benzene ring and also contains a pi bond and the external group hydroxyl group (-OH) has a high electron cloud density, the anthocyanin-like organic molecule has electron withdrawing and electron transporting properties in the solid film, thereby enhancing the device efficiency and lifetime of the quantum dot light emitting diode. In addition, a large number of hydroxyl (-OH) groups externally connected with the anthocyanin-like organic molecules and functional groups on the surface of the metal oxide nano particles form hydrogen bonds, so that the effective adhesion and crosslinking effects can be achieved, and the stability of the solid film is improved.

The organic molecule can also be furan series compound organic molecule, when the molecule and the metal oxide nano-particles form a solid film, one pair of lone-pair electrons of oxygen atom in the furan series compound organic molecule forms a large pi bond in a conjugated orbit plane, and the other pair of lone-pair electrons of the oxygen atom extends outwards and has an electron-donating effect. Therefore, after the furan-based compound organic molecules and the metal oxide nanoparticles are used for forming the solid film, the adsorption of the conductive electrons of the metal oxide nanoparticles by hydrogen in hydrogen bonds can be effectively reduced. By adopting the mode, the charge transmission performance of the metal oxide nanoparticle solid film can be effectively improved, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

In one embodiment, the ratio of the organic molecule to the metal oxide nanoparticles is (0.1 to 10mmol):100 mg. The composite formed under the ratio is used as a charge transport material, and the conductivity of the metal oxide solid film can be effectively improved. Too much (anthocyanin-like organic molecules) may hinder the conductivity of the membrane, and too little may not be effective in improving the membrane.

In this embodiment, the anthocyanin-like organic molecule has a structural characteristic that the molecule contains benzene rings and pi bonds and the periphery contains more hydroxyl functional groups. In one embodiment, the anthocyanin-like organic molecule includes one or more of procyanidins, anthocyanins rhamnoside, procyanidin B, and the like.

In this embodiment, the structural feature of the organic molecule of the furan compound is that a pair of lone-pair electrons of oxygen atom in the molecule forms a large pi bond in the plane of the conjugated orbit, and the other lone-pair electrons of oxygen atom extend outward and have an electron donating effect. In one embodiment, the furan-based compound organic molecule comprises one or more of furan, 3-methylfuran, nitrofural, 2-ethylfuran, furanone, furan-3-methanol, and the like.

In a specific embodiment, the complex is composed of an anthocyanin-like organic molecule and metal oxide nanoparticles, the ratio of the anthocyanin-like organic molecule to the metal oxide nanoparticles is 0.5mmol:100mg, the anthocyanin-like organic molecule is procyanidin, and the metal oxide nanoparticles are ZnO nanoparticles. The composite of the embodiment can be used as a charge transport material, and can effectively improve the charge transport performance of the metal oxide nanoparticle solid film, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

In a specific embodiment, the complex is composed of an anthocyanin-like organic molecule and metal oxide nanoparticles, wherein the ratio of the anthocyanin-like organic molecule to the metal oxide nanoparticles is 2mmol:100mg, the anthocyanin-like organic molecule is procyanidin B, and the metal oxide nanoparticles are NiO nanoparticles. The composite of the embodiment can be used as a charge transport material, and can effectively improve the charge transport performance of the metal oxide nanoparticle solid film, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

In a specific embodiment, the composite is composed of furan-based compound organic molecules and metal oxide nanoparticles, wherein the ratio of the furan-based compound organic molecules to the metal oxide nanoparticles is 5mmol:100mg, the furan-based compound organic molecules are furan, and the metal oxide nanoparticles are ZnO nanoparticles. The composite of the embodiment can be used as a charge transport material, and can effectively improve the charge transport performance of the metal oxide nanoparticle solid film, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

In a specific embodiment, the composite is composed of furan-based compound organic molecules and metal oxide nanoparticles, the ratio of the furan-based compound organic molecules to the metal oxide nanoparticles is 8mmol:100mg, the furan-based compound organic molecules are a mixture of 3-methylfuran and 2-ethylfuran, and the metal oxide nanoparticles are SnO nanoparticles. The composite of the embodiment can be used as a charge transport material, and can effectively improve the charge transport performance of the metal oxide nanoparticle solid film, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

In a specific embodiment, the compound consists of furan-based compound organic molecules and metal oxide nanoparticles, the ratio of the furan-based compound organic molecules to the metal oxide nanoparticles is 1mmol:100mg, the furan-based compound organic molecules is nitrofural, and the metal oxide nanoparticles are W₂O₃And mixed particles of SnO. The composite of the embodiment can be used as a charge transport material, and can effectively improve the charge transport performance of the metal oxide nanoparticle solid film, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

The embodiment of the invention provides a quantum dot light-emitting diode which comprises an anode, a quantum dot light-emitting layer, an electron transmission layer and a cathode, wherein the quantum dot light-emitting layer is arranged between the anode and the cathode, the electron transmission layer is arranged between the quantum dot light-emitting layer and the cathode, the electron transmission layer comprises organic molecules and metal oxide nanoparticles, and the organic molecules are anthocyanin-like organic molecules or furan compound organic molecules.

In one embodiment, the electron transport layer is comprised of organic molecules and metal oxide nanoparticles.

In one embodiment, the ratio of the organic molecule to the metal oxide nanoparticles is (0.1 to 10mmol):100 mg. At this ratio, the conductivity of the metal oxide solid film can be effectively improved. Too much (anthocyanin-like organic molecules) may hinder the conductivity of the membrane, and too little may not be effective in improving the membrane.

In one embodiment, the metal oxide nanoparticles comprise ZnO, NiO, W₂O₃、Mo₂O₃、TiO₂、SnO、ZrO₂And Ta₂O₃And the like.

In one embodiment, the metal oxide nanoparticles are aqueous phase nanoparticles.

In one embodiment, the metal oxide nanoparticles are n-type semiconductor nanoparticles. The n-type semiconductor nano-particles have higher electron mobility, so that the electron transmission can be effectively realized.

In one embodiment, the thickness of the electron transport layer is 5 to 200 nm. In this range, high electron mobility can be effectively achieved, which is advantageous in obtaining a highly efficient device.

In one embodiment, the quantum dot light emitting diode may further include a hole function layer disposed between the anode and the quantum dot light emitting layer. Wherein the hole function layer may be selected from one or both of a hole injection layer and a hole transport layer. When the hole function layer is a hole injection layer or a hole transport layer, the hole transport layer is attached to the quantum dot light emitting layer.

In one embodiment, the material of the hole injection layer is a material having good hole injection properties, and may include, for example, but not limited to, one or more of poly (3, 4-ethylenedioxythiophene) -polystyrenesulfonic acid (PEDOT: PSS), copper phthalocyanine (CuPc), 2,3,5, 6-tetrafluoro-7, 7',8,8' -tetracyanoquinodimethane (F4-TCNQ), 2,3,6,7,10, 11-hexacyano-1, 4,5,8,9, 12-Hexaazatriphenylene (HATCN), transition metal oxide, transition metal chalcogenide compound; wherein the transition metal oxide may include, but is not limited to NiO_x、MoO_x、WO_x、CrO_xAnd CuO; the metal chalcogenide compound may include, but is not limited to, MoS_x、MoSe_x、WS_x、WSe_xAnd CuS.

In one embodiment, the material of the hole transport layer is an organic material having good hole transport ability, and may include, for example, but not limited to, Poly (9, 9-dioctylfluorene-CO-N- (4-butylphenyl) diphenylamine) (TFB), Polyvinylcarbazole (PVK), Poly (N, N 'bis (4-butylphenyl) -N, N' -bis (phenyl) benzidine) (Poly-TPD), Poly (9, 9-dioctylfluorene-CO-bis-N, N-phenyl-1, 4-Phenylenediamine) (PFB), 4', 4 ″ -tris (carbazol-9-yl) triphenylamine (TCTA), 4' -bis (9-Carbazole) Biphenyl (CBP), N '-diphenyl-N, N' -bis (3-methylphenyl) -1, one or more of 1 '-biphenyl-4, 4' -diamine (TPD), N '-diphenyl-N, N' - (1-naphthyl) -1,1 '-biphenyl-4, 4' -diamine (NPB), graphene, and C60.

In a preferred embodiment, the hole transport layer may also be an inorganic material with hole transport capability, such as but not limited to NiO_x、MoO_x、WO_x、CrO_x、CuO、MoS_x、MoSe_x、WS_x、WSe_xAnd CuS.

In one embodiment, the material of the quantum dot light emitting layer may include, but is not limited to, one or more of group II-VI compounds, group III-V compounds, group II-V compounds, group III-VI compounds, group IV-VI compounds, group I-III-VI compounds, group II-IV-VI compounds, or group IV elements. By way of example, the material of the quantum dot light emitting layer may include, but is not limited to, one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, PbS, PbSe, PbTe, and other binary, ternary, quaternary II-VI compounds; by way of example, the material of the quantum dot light emitting layer may include, but is not limited to, one or more of GaP, GaAs, InP, InAs, and other binary, ternary, quaternary III-V compounds.

In one embodiment, the material of the quantum dot light emitting layer may also be a doped or undoped inorganic perovskite type semiconductor, and/or an organic-inorganic hybrid perovskite type semiconductor. Wherein the structural general formula of the inorganic perovskite type semiconductor is AMX₃Wherein A is Cs⁺Ions; m is a divalent metal cation, and may be selected from, but is not limited to, Pb²⁺、Sn²⁺、Cu²⁺、Ni²⁺、Cd²⁺、Cr²⁺、Mn²⁺、Co²⁺、Fe²⁺、Ge²⁺、Yb²⁺Or Eu²⁺(ii) a X is a halide anion, and can be selected from but not limited to Cl^-、Br^-Or I^-. Wherein the structural general formula of the organic-inorganic hybrid perovskite type semiconductor is BMX₃Wherein B is an organic amine cation, and may be selected from, but is not limited to, CH₃(CH₂)_n-2NH₃⁺(n.gtoreq.2) or NH₃(CH₂)_nNH₃²⁺(n is more than or equal to 2); when n is 2, the inorganic metal halide octahedron MX₆^4-The metal cations M are positioned in the center of a halogen octahedron through connection in a roof sharing mode, and the organic amine cations B are filled in gaps among the octahedrons to form an infinitely extending three-dimensional structure; inorganic metal halide octahedra MX linked in a coterminous manner when n > 2₆^4-The organic amine cation bilayer (protonated monoamine) or the organic amine cation monolayer (protonated diamine) is inserted between the layers, and the organic layer and the inorganic layer are overlapped with each other to form a stable two-dimensional layered structure; m is twoThe valent metal cation may be selected from, but is not limited to, Pb²⁺、Sn²⁺、Cu²⁺、Ni²⁺、Cd²⁺、Cr²⁺、Mn²⁺、Co²⁺、Fe²⁺、Ge²⁺、Yb²⁺、Eu²⁺(ii) a X is a halide anion, and can be selected from but not limited to Cl^-、Br^-Or I^-。

It should be noted that the quantum dot light emitting diode may further include an interface modification layer, and the interface modification layer may be one or more layers selected from an electron blocking layer, a hole blocking layer, an electron injection layer, an electrode modification layer, and an isolation protection layer.

In this embodiment, the quantum dot light emitting diode may be packaged partially, fully or not.

Fig. 2 is a schematic flow chart of a method for manufacturing a quantum dot light emitting diode according to an embodiment of the present invention, as shown in fig. 2, including:

s21, providing an anode, and preparing a quantum dot light-emitting layer on the anode;

s22, preparing an electron transport layer on the quantum dot light-emitting layer;

s23, preparing a cathode on the electron transport layer to obtain the quantum dot light-emitting diode;

Fig. 3 is a schematic flow chart of a method for manufacturing a quantum dot light emitting diode according to another embodiment of the present invention, as shown in fig. 3, including:

s31, providing a cathode, and preparing an electron transport layer on the cathode;

s32, preparing a quantum dot light-emitting layer on the electron transport layer;

s33, preparing an anode on the quantum dot light-emitting layer to obtain the quantum dot light-emitting diode;

In this embodiment, each layer deposition method may be a chemical method or a physical method, wherein the chemical method includes, but is not limited to, one or more of a chemical vapor deposition method, a continuous ion layer adsorption and reaction method, an anodic oxidation method, an electrolytic deposition method, and a coprecipitation method; the physical method includes, but is not limited to, one or more of spin coating, printing, knife coating, dip coating, dipping, spraying, roll coating, casting, slit coating, bar coating, thermal evaporation, electron beam evaporation, magnetron sputtering, multi-arc ion coating, physical vapor deposition, atomic layer deposition, and pulsed laser deposition.

In one embodiment, the method of making the electron transport layer comprises:

providing an organic molecule and metal oxide nanoparticles;

depositing the mixed solution on the quantum dot light-emitting layer to obtain the electron transmission layer;

or depositing the mixed solution on the cathode to obtain the electron transport layer.

In the above embodiment, the mixing conditions are related to the mixing amount of the organic molecule and the metal oxide nanoparticles, the temperature, the time, and the environment.

In a preferred embodiment, the ratio of the organic molecule to the metal oxide nanoparticles in the mixed solution is (0.1 to 10mmol):100 mg.

In a preferred embodiment, the temperature of the mixing is 20 to 100 ℃. The dissolution of organic molecules can be efficiently achieved in this temperature range.

In a preferred embodiment, the mixing time is 5 to 60 min. Sufficient mixing of the organic molecules with the metal oxide nanoparticles can be effectively achieved within this time frame.

In a preferred embodiment, the mixed environment is an inert atmosphere.

In a preferred embodiment, the concentration of the metal oxide nanoparticles in the mixed solution is 5 to 60 mg/ml.

In a preferred embodiment, the solvent is a polar solvent, and may include, but is not limited to, one or more of an alcohol solvent, a nitrile solvent, and derivatives thereof. Particularly preferably, the solvent is an alcoholic solvent, and may include, but is not limited to, one or more of monohydric alcohol, polyhydric alcohol, and aromatic alcohol, and specifically may include, but is not limited to, one or more of methanol, ethanol, ethylene glycol, propanol, propylene glycol, glycerol, isopropanol, butanol, pentanol, hexanol, cyclohexanol, n-butanol, benzyl alcohol, and phenethyl alcohol.

The present invention will be described in detail below with reference to specific examples.

Example 1

1) Mixing ZnO nanoparticles with procyanidine:

dissolving 0.5mmol procyanidin (structure formula shown in figure 4) in 5ml ethanol solution, adding 100mg ZnO nanoparticles into ethanol solution containing procyanidin, and heating and stirring at 50 deg.C for 30min under inert gas protection to obtain uniform mixed solution.

2) Preparing a solid film by using a mixed solution of ZnO nanoparticles and procyanidine:

a layer of ZnO nano-particle solid film containing procyanidine is prepared on a clean glass substrate in a spin coating mode at a proper rotating speed, and then the solid film is annealed at 80 ℃.

Preparing a quantum dot light-emitting diode:

preparing a hole transport layer, a quantum dot light emitting layer, an electron transport layer and a cathode on a clean glass substrate (containing an anode) in sequence; wherein, the preparation of the electron transport layer is obtained by the steps 1) and 2).

Example 2

1) Mixing ZnO nanoparticles with furan:

dissolving 0.5mmol furan (formula shown in figure 5) in 5ml ethanol solution, adding 100mg ZnO nanoparticles into the ethanol solution containing furan, and heating and stirring at 50 deg.C for 30min under inert gas protection to obtain uniform mixed solution.

2) Preparing a solid film by using a mixed solution of ZnO nanoparticles and furan:

a layer of ZnO nano-particle solid film containing furan is prepared on a clean glass substrate by adopting a spin coating mode at a proper rotating speed, and then the solid film is annealed at 80 ℃.

Preparing a quantum dot light-emitting diode:

In summary, the invention provides a compound, a preparation method thereof and a quantum dot light emitting diode. Specifically, the organic molecule can be an anthocyanin-containing organic molecule, when the molecule and the metal oxide nanoparticles form a solid film, a functional group on the surface of the metal oxide nanoparticles can form a hydrogen bond with a hydroxyl (-OH) group in an anthocyanin-like organic molecule, and the anthocyanin-like organic molecule also contains a pi bond due to the benzene ring contained in the anthocyanin-like organic molecule and has high electron cloud density of the hydroxyl (-OH) group externally connected, so the anthocyanin-like organic molecule has the performance of electron absorption and electron transmission. In addition, a large number of hydroxyl (-OH) groups externally connected with the anthocyanin-like organic molecules and functional groups on the surface of the metal oxide nano particles form hydrogen bonds, so that the effective adhesion and crosslinking effects can be achieved, and the stability of the solid film is improved. The organic molecule can also be furan series compound organic molecule, when the molecule and the metal oxide nano-particles form a solid film, one pair of lone-pair electrons of oxygen atom in the furan series compound organic molecule forms a large pi bond in a conjugated orbit plane, and the other pair of lone-pair electrons of the oxygen atom extends outwards and has an electron-donating effect. Therefore, after the furan-based compound organic molecules and the metal oxide nanoparticles are used for forming the solid film, the adsorption of the conductive electrons of the metal oxide nanoparticles by hydrogen in hydrogen bonds can be effectively reduced. By adopting the mode, the charge transmission performance of the metal oxide nanoparticle solid film can be effectively improved, so that the device efficiency and the service life of the quantum dot light-emitting diode are enhanced.

It is to be understood that the invention is not limited to the examples described above, but that modifications and variations may be effected thereto by those of ordinary skill in the art in light of the foregoing description, and that all such modifications and variations are intended to be within the scope of the invention as defined by the appended claims.

Claims

1. A method of preparing a composite, comprising:

and heating the mixed solution to obtain the compound.

2. The method for preparing the composite according to claim 1, wherein in the step of mixing the organic molecule, the metal oxide nanoparticles and the solvent, the temperature of the mixing is 20 to 100 ℃; and/or

The mixing time is 5-60 min.

3. The method for preparing a composite according to claim 1, wherein the ratio of the organic molecule to the metal oxide nanoparticles in the mixed solution is (0.1 to 10mmol):100 mg; and/or

In the mixed solution, the concentration of the metal oxide nanoparticles is 5-60 mg/ml.

4. A composite comprising an organic molecule and metal oxide nanoparticles, wherein the organic molecule is an anthocyanin-like organic molecule or a furan-based compound organic molecule.

5. The composite of claim 4, wherein the composite is comprised of organic molecules and metal oxide nanoparticles.

6. The composite of claim 4, wherein the ratio of organic molecules to metal oxide nanoparticles is (0.1-10 mmol):100 mg.

7. The complex of claim 4, wherein the anthocyanin-like organic molecule comprises one or more of procyanidins, anthocyanins rhamnoside, and procyanidin B.

8. The composite of claim 4, wherein the furan-based compound organic molecule comprises one or more of furan, 3-methylfuran, nitrofurazone, 2-ethylfuran, furanone, and furan-3-methanol.

9. A quantum dot light-emitting diode comprises an anode, a quantum dot light-emitting layer, an electron transmission layer and a cathode, wherein the quantum dot light-emitting layer is arranged between the anode and the cathode, and the electron transmission layer is arranged between the quantum dot light-emitting layer and the cathode.

10. The quantum dot light-emitting diode of claim 9, wherein the electron transport layer is composed of organic molecules and metal oxide nanoparticles.

11. The quantum dot light-emitting diode of claim 9, wherein the ratio of the organic molecules to the metal oxide nanoparticles is (0.1-10 mmol):100 mg.

12. The quantum dot light-emitting diode of claim 9, wherein the anthocyanin-like organic molecule comprises one or more of procyanidins, anthocyanidins rhamnoside, and procyanidin B.

13. The quantum dot light-emitting diode of claim 9, wherein the furan-based compound organic molecule comprises one or more of furan, 3-methylfuran, nitrofurazone, 2-ethylfuran, furanone, and furan-3-methanol.

14. The quantum dot light-emitting diode of claim 9, wherein the thickness of the electron transport layer is 5 to 200 nm.